<?php

namespace GetId3\Write;

use GetId3\Lib\Helper;
use GetId3\GetId3Core;
use GetId3\Module\Tag;

/////////////////////////////////////////////////////////////////
/// GetId3() by James Heinrich <info@getid3.org>               //
//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details                             //
/////////////////////////////////////////////////////////////////
//                                                             //
// write.id3v1.php                                             //
// module for writing ID3v1 tags                               //
// dependencies: module.tag.id3v1.php                          //
//                                                            ///
/////////////////////////////////////////////////////////////////

/**
 * module for writing ID3v1 tags
 *
 * @author James Heinrich <info@getid3.org>
 *
 * @link http://getid3.sourceforge.net
 * @link http://www.getid3.org
 *
 * @uses GetId3\Module\Tag\Id3v1
 */
class Id3v1
{
    public $filename;
    public $filesize;
    public $tag_data;
    /**
     * @var array
     */
    public $warnings = array(); // any non-critical errors will be stored here
    /**
     * @var array
     */
    public $errors = array(); // any critical errors will be stored here

    /**
     * @return bool
     */
    public function __construct()
    {
        return true;
    }

    /**
     * @return bool
     */
    public function WriteID3v1()
    {
        // File MUST be writeable - CHMOD(646) at least
        if (!empty($this->filename) && is_readable($this->filename) && is_writable($this->filename) && is_file($this->filename)) {
            $this->setRealFileSize();
            if (($this->filesize <= 0) || !Helper::intValueSupported($this->filesize)) {
                $this->errors[] = 'Unable to WriteID3v1('.$this->filename.') because filesize ('.$this->filesize.') is larger than '.round(PHP_INT_MAX / 1073741824).'GB';

                return false;
            }
            if ($fp_source = fopen($this->filename, 'r+b')) {
                fseek($fp_source, -128, SEEK_END);
                if (fread($fp_source, 3) == 'TAG') {
                    fseek($fp_source, -128, SEEK_END); // overwrite existing ID3v1 tag
                } else {
                    fseek($fp_source, 0, SEEK_END);    // append new ID3v1 tag
                }
                $this->tag_data['track'] = (isset($this->tag_data['track']) ? $this->tag_data['track'] : (isset($this->tag_data['track_number']) ? $this->tag_data['track_number'] : (isset($this->tag_data['tracknumber']) ? $this->tag_data['tracknumber'] : '')));

                $new_id3v1_tag_data = Tag\Id3v1::GenerateID3v1Tag(
                                                        (isset($this->tag_data['title']) ? $this->tag_data['title']   : ''),
                                                        (isset($this->tag_data['artist']) ? $this->tag_data['artist']  : ''),
                                                        (isset($this->tag_data['album']) ? $this->tag_data['album']   : ''),
                                                        (isset($this->tag_data['year']) ? $this->tag_data['year']    : ''),
                                                        (isset($this->tag_data['genreid']) ? $this->tag_data['genreid'] : ''),
                                                        (isset($this->tag_data['comment']) ? $this->tag_data['comment'] : ''),
                                                        (isset($this->tag_data['track']) ? $this->tag_data['track']   : ''));
                fwrite($fp_source, $new_id3v1_tag_data, 128);
                fclose($fp_source);

                return true;
            } else {
                $this->errors[] = 'Could not fopen('.$this->filename.', "r+b")';

                return false;
            }
        }
        $this->errors[] = 'File is not writeable: '.$this->filename;

        return false;
    }

    /**
     * @return bool
     */
    public function FixID3v1Padding()
    {
        // ID3v1 data is supposed to be padded with NULL characters, but some taggers incorrectly use spaces
        // This function rewrites the ID3v1 tag with correct padding

        // Initialize GetId3 engine
        $getID3 = new GetId3Core();
        $getID3->option_tag_id3v2 = false;
        $getID3->option_tag_apetag = false;
        $getID3->option_tags_html = false;
        $getID3->option_extra_info = false;
        $getID3->option_tag_id3v1 = true;
        $ThisFileInfo = $getID3->analyze($this->filename);
        if (isset($ThisFileInfo['tags']['id3v1'])) {
            foreach ($ThisFileInfo['tags']['id3v1'] as $key => $value) {
                $id3v1data[$key] = implode(',', $value);
            }
            $this->tag_data = $id3v1data;

            return $this->WriteID3v1();
        }

        return false;
    }

    public function RemoveID3v1()
    {
        // File MUST be writeable - CHMOD(646) at least
        if (!empty($this->filename) && is_readable($this->filename) && is_writable($this->filename) && is_file($this->filename)) {
            $this->setRealFileSize();
            if (($this->filesize <= 0) || !Helper::intValueSupported($this->filesize)) {
                $this->errors[] = 'Unable to RemoveID3v1('.$this->filename.') because filesize ('.$this->filesize.') is larger than '.round(PHP_INT_MAX / 1073741824).'GB';

                return false;
            }
            if ($fp_source = fopen($this->filename, 'r+b')) {
                fseek($fp_source, -128, SEEK_END);
                if (fread($fp_source, 3) == 'TAG') {
                    ftruncate($fp_source, $this->filesize - 128);
                } else {
                    // no ID3v1 tag to begin with - do nothing
                }
                fclose($fp_source);

                return true;
            } else {
                $this->errors[] = 'Could not fopen('.$this->filename.', "r+b")';
            }
        } else {
            $this->errors[] = $this->filename.' is not writeable';
        }

        return false;
    }

    /**
     * @return bool
     */
    public function setRealFileSize()
    {
        if (PHP_INT_MAX > 2147483647) {
            $this->filesize = filesize($this->filename);

            return true;
        }
        // 32-bit PHP will not return correct values for filesize() if file is >=2GB
        // but GetId3->analyze() has workarounds to get actual filesize
        $getID3 = new GetId3Core();
        $getID3->option_tag_id3v1 = false;
        $getID3->option_tag_id3v2 = false;
        $getID3->option_tag_apetag = false;
        $getID3->option_tags_html = false;
        $getID3->option_extra_info = false;
        $ThisFileInfo = $getID3->analyze($this->filename);
        $this->filesize = $ThisFileInfo['filesize'];

        return true;
    }
}
